1. Field of the Invention
The present invention relates, in general, to electrical apparatus and, specifically, to electrical watthour meter socket adapters and related watthour meter apparatus.
2. Description of the Art
In the electric utility industry, plug-in, socket-type watthour meters are commonly employed to measure electric power consumption at a residential or commercial building establishment. A socket is mounted on a wall of the residence or building and contains terminals which are connected to electric line and electric load conductors. The terminals are also connected to internal conductors within the socket which extend to jaw contacts positioned to receive the blade terminals of a plug-on watthour meter to complete an electric circuit through the watthour meter between the line and load terminals and the conductors.
One type of meter socket has a ring-type cover which includes an outwardly projecting, annular mounting flange surrounding an opening in the cover through which the blade terminals of a watt hour meter extend. The mounting flange is sized to mate with a complementary formed mounting flange on the bottom of the watthour meter.
Another type of meter socket known as a ringless or clamp jaw socket has an aperture in the socket cover sized to secure the meter flange within the socket cover. The shell of the socket adapter, after the socket adapter is mounted in the jaw contacts of the watthour meter socket, extends through the aperture in the socket cover and receives a watthour meter in a snap-in connection.
It is common to add various additional features and components to a meter service application, such as surge suppression, circuit breakers, automatic meter reading, communication systems, etc., which the service was not originally designed to accept or utilize. Such components have often been mounted in a separate enclosure or receptacle which is attached to an existing watthour socket adapter, or built in to the interior of the socket adapter with special modifications to the shell and/or terminal portions of the adapter to provide sufficient space to house the additional components.
In certain meter sockets, such as ringless or clamp jaw sockets, there is insufficient aperture size in the meter socket cover to enable an enlarged socket adapter or a socket adapter having a separate receptacle or enclosure mounted thereon to fit through the socket cover meter aperture.
One solution to this problem utilizes a conventional watthour meter socket adapter/extender which is connected to the jaw contacts in a watthour meter socket. The shell portion of the socket adapter/extender extends outward through the aperture in the ringless-style watthour meter socket cover. A separate housing containing additional features or components is attached to a bottom portion of the shell by means of screws extending through adjacent surfaces on the socket adapter/extender shell and the separate housing. Aligned apertures in the shell and the enclosure allow for the passage of electrical conductors between the conductive elements in the watthour meter socket adapter and components or terminals in the separate housing.
This solution, however, is not without problems. Although the housing containing additional features is accessible separately from the watthour meter mounted in the socket adapter/extender to enable replacement or updating of the additional features without removing the watthour meter, any removal or mounting of the housing to or from the shell of the socket adapter/extender typically requires the removal of the watthour meter from the socket adapter/extender. Industry standards require that the watthour meter can only be removed by an authorized utility company serviceman. The authorized utility company serviceman is the only individual who is authorized to remove the seals indicating non-tampering of the watthour meter and/or the socket adapter/extender. Thus, two servicemen, one to remove the watthour meter and the other to service the additional features, may be required for a single service entrance. Also the power to the service will be disconnected requiring the customer to reset electrical or electronic devices due to the power outage.
Solutions to these problems are described hereafter.